As a technology of manufacturing a three-dimensional object, there is known a deposition shaping technology of manufacturing a three-dimensional object by irradiating a metallic powder material with a light beam. For example, Patent Literature 1 discloses a method in which a powder layer formed of a metallic powder material is irradiated with a light beam so that a sintered layer is formed and this process is repeated so that a plurality of sintered layers are integrally deposited to form a three-dimensional object.